


When Life Give Hulk Lemon, Hulk Eat It and say GIVE HULK MORE LEMONS

by Blizzard_Fire



Series: Science Bros Week 2019 [3]
Category: Marvel Cinematic Universe
Genre: Adorable Bruce Banner, Adorable Hulk (Marvel), Bruce has a very specific allergy, Domestic Fluff, Fluff, Hulk Talks (Marvel), Humor, M/M, Tony and Hulk bonding, Wingman Hulk
Language: English
Status: Completed
Published: 2019-07-28
Updated: 2019-07-28
Packaged: 2020-07-08 16:44:04
Rating: Teen And Up Audiences
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 2,879
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/19872796
Author URL: https://archiveofourown.org/users/Blizzard_Fire/pseuds/Blizzard_Fire
Summary: Bruce keeps Hulking out with no memory of why it happens. The result: Tony and Hulk have some unexpected bonding time.Also lemons.





	When Life Give Hulk Lemon, Hulk Eat It and say GIVE HULK MORE LEMONS

**Author's Note:**

> Written for the prompt "bitter" for Science Bros Week 2019. Tony and Hulk don't seem to hang out much and you know Tony would be pretty chill with him.

The first time it happened, Tony had ventured to the communal kitchen for a 3am snack.

The lights remained dim as he wandered in, humming the theme tune from some video game Clint had been playing earlier. Eyes half-closed, he rummaged in the fridge and pulled out a Tupperware box of ice-cold blueberries.

'Hulk have some?'

Tony yelped and dropped the box, sending blueberries skittering into the dark. A large green head peered over the top of the fridge door, looking hesitant. 'Holy shit, give me some warning will you? Don't just sneak up on people like that.' He closed the fridge.

'Hulk sorry.' He continued to stare at him expectantly, as though waiting for something.

'What are you doing out, big guy? Bruce having nightmares or something?' Though Tony had never known him to go green in his sleep.

Hulk shrugged his broad shoulders. 'Hulk just woke up. Nothing to smash.' He pointed at the floor. 'Hulk have some?' he repeated.

Tony sighed. 'Knock yourself out, buddy.' As Hulk sat down on the floor and started picking up blueberries, Tony saw something he really wasn't prepared to see at this time of night. 'Woah! I'm guessing Bruce's pyjamas don't stretch too well.'

There wasn't a scrap of clothing on Hulk's huge body. Tony quickly averted his eyes, the phrase "two grapefruits and a cucumber" coming swiftly to mind.

'Banner sleep naked. Feel better.'

He filed that thought away for later inspection. It was nice to think that Bruce now felt safe enough here to let his guard down at night. Nice to think that... Bruce slept naked. 'Okay, well I'm going back to bed. Can I trust you to behave?'

Hulk grunted an affirmative, now preoccupied with digging out a blueberry from under the fridge.

Still uncertain this wasn't all a bizarre dream, Tony went back to bed.

The next morning, Bruce made no mention of the incident, though he claimed to have slept badly. Tony might indeed have passed it off as a dream, except for the absence of his blueberries and the large purple smudge on the floor.

The second time it happened, Tony was in his workshop with the stereo blasting AC/DC.

_'Sir, you have a visitor.'_

He set the screwdriver down on the table to pick up a smaller one. 'Show em in. Unless it's Cap. Otherwise tell him I'm busy.'

The music was so loud that at first he didn't register the slow, heavy footsteps. Then he looked up and was faced with a bashful-looking Hulk, once again in the nude and looking baffled as to why he was here. 'No fight?' he asked when Tony turned the music down.

'Not today, no.' Tony pulled up his goggles. 'Bruce just randomly Hulk out again?'

He grunted and nodded, looking around the workshop with interest. He picked up a silver coffee maker, turning it to study his reflection.

'That's just a little project I'm working on. Bruce likes his coffee so I'm giving this one a little something extra. I'm working on a new AI for it, obviously not as smart as JARVIS but I'm thinking something that can talk physics with him. Failing that, something that can tell physics jokes. Still working on the acronym of course...' He stopped at the blank expression on Hulk's face. 'Not important. You know what _is_ important?' He walked out from behind the workbench to rummage through his shelves. 'Keeping that big green butt of yours warm.' He pulled out a pair of Hulk-sized pants. 'I updated the design, should be even more comfortable now. Give those a go.'

'Hulk not get cold.' He shrugged, but caught the pair as they were tossed to him.

Tony noticed that his hair was dripping wet, his green skin shiny with water. 'Did you transform in the shower?'

Hulk hung his head. 'Shower not big enough, Hulk broke it. Banner keep changing but nothing to smash.' He pulled on the pants.

So Bruce had transformed whilst naked in the shower, then again, late at night, naked in bed... 'I think I have a theory,' he said, wandering back to his workplace. Hadn't Bruce once said something about keeping his heart rate down? But surely he knew that getting himself off was causing Hulk-outs? Maybe he needed to have a talk with him. 'I never liked that shower, anyway. I'll build it bigger next time, would you like that?'

Hulk was still hovering by the door, eyes narrowed with interest at the stereo. His big green toes tapped out a rhythm on the floor.

'You like music, big guy?' Tony cranked up the volume to _Shoot to Thrill._ 'Could use some company while I work?'

Hulk sat down on the floor, legs crossed, and happily bopped his head to the music. 'Banner hate this song,' he said thoughtfully.

'What Banner doesn't know won't hurt him.' It wasn't Hulk's fault he was here so Tony wasn't about to make him feel unwanted. Hulk was content to sit and listen to music until Tony was finished, and before he left Hulk actually held up his hand for a high-five. 'See ya round, big green. Hopefully next time it wasn't be a false alarm.'

Hulk nodded and smiled, then he frowned as if trying to remember something. 'Banner like you,' he said finally. 'Good friend. Banner think about you a lot.'

And dammit if Tony didn't spend the rest of the day wondering exactly what that meant.

The third time it happened, Tony didn't see a naked Hulk. Instead there was a naked Bruce.

' _Sir, your assistance is required urgently in the lab.'_

Tony sighed and made his way over with a sneaking suspicion of what he would find. But by the time he reached the lab the incident was over.

A worktable was overturned, chemicals spilled over the floor. The sink tap was still running, a bottle of handwash dribbling its contents over the floor. And lying in the middle of it all was Bruce, loosely covered in a torn lab coat. He blinked fuggily up at Tony. 'What happened? Did something explode?'

'Just you, looks like.' Tony offered a hand.

Bruce took it and pulled himself up. The lab coat slid off. He fumbled to grab it and cover himself, cheeks reddening. 'I don't remember why I changed,' he said in horror. 'Normally I know when it's happening, but...'

'Like in the shower?' Tony prompted. When Bruce had told him about the broken shower he'd pretended to be surprised, choosing not to mention his little chat with Hulk.

'Yeah.' He rubbed his face with a hand. 'This isn't normal, Tony. I don't know why it keeps happening.'

'We'll get to the bottom of it.' He reached out to sling an arm over his shoulders, then remembered Bruce was naked. 'At least the big guy hasn't been doing much damage, right?'

Bruce just stood there looking dazed, trying in vain to cover both the front and back of himself and settling for simply facing Tony with the balled-up fabric held against his crotch. 'I don't wanna hurt anyone,' he whispered.

'You won't. Hulk's not stupid; he knows he's among friends here.' There was no way Bruce had been jerking off in the lab, so Tony's latest theory was out of the window. Hulk was as confused as Bruce, so it wasn't a power struggle.

So what else could cause Bruce, the master of self-control, to constantly Hulk-out without knowing it?

Stark Tower's kitchen had all the latest gadgetry. It could make you a three-course meal and teach you Italian whilst it did so. But sometimes even Tony felt like a break from machines, so he'd spent the whole morning cooking up some recipes.

'You're... baking?'

Tony shrugged without turning around. 'You got a problem with me baking?'

Bruce laughed softly. 'No, it's just... I thought you'd have a machine to do it for you.' As if to emphasise his point, he padded over to the shiny new coffee maker, which poured him a brew.

'Working helps me think.' He'd hit some snags on a project, so the kitchen had basically become his workshop.

The coffee maker beeped. ' _Your coffee is ready!'_ it chirruped. ' _Hey, how many theoretical physicists does it take to change a lightbulb?'_

Tony glanced back in time to catch Bruce's bemused expression. 'Uh, I don't know?'

_'Two. One to hold the bulb and the other to rotate the universe.'_

Slowly, a smile crept across Bruce's face. 'That's pretty good. Tony, what is this?'

'Oh, just a little side project of mine.' He turned away and set about cracking eggs into a bowl. 'Does Everything: Coffee and Fun. DECAF for short.'

_'Would you like to hear another?'_

'No thanks, DECAF.' He wandered over to Tony, eyeing the finished goods sitting on the counter. 'How long have you been here? Is there a Stark bake sale I should know about?' There were brownies, cakes, a yellow pie (with a piece already missing from when Tony got hungry earlier), and a scattering of smaller pastries.

'Help yourself.' He waved a hand, secretly pleased to see Bruce look impressed. 'Before the others get here and eat it all.'

'Don't mind if I do.' He delved in the kitchen drawer and pulled out a knife, cutting himself a piece of the pie.

'Made any progress on your little green problem?'

He pulled a face. 'Don't call it that. And no, I haven't. I can't think of anything that links them.' He pulled out a spoon and ate a large bite. Then he frowned, still chewing. 'What's in this?'

'Uh, flour, eggs, lemons - '

Bruce clasped a hand to his mouth, too late to prevent himself from swallowing it. 'Lemons?'

'Well yeah, it's a lemon pie.' He put the bowl down. 'Why?'

'I thought it was custard.' Bruce dropped the plate on the counter with a clatter. 'Shit, this is bad.' His lips pressed together. 'I don't know how my body's going to react, I haven't had to deal with this since the other guy. Tony, I don't - I don't know what to do...'

Tony could only stare at him. 'What did I do?'

DECAF's lights flashed. ' _Would you like to hear another joke? A scientist used a flux capacitor as a doorstop...'_

Bruce fell to his knees, groaning as his shirt ripped and Hulk's green muscles tore through.

_'His friend told him, "weird flux, but okay".'_

'It's a learning AI,' Tony babbled, 'think that was some Gen Z humour, I didn't get it either - um, are you okay?'

Hulk scowled up at him. 'No bad guys?'

Tony picked up the plate that Bruce had dropped, sniffing it. 'JARVIS, what the hell was that? Did the _pie_ cause this?'

 _'It seems that Doctor Banner has a citrus allergy. He may experience an allergic reaction from consuming or touching lemons, grapefruits, pineapples and so on.'_

'Oh. But that doesn't explain all the other times. Bruce isn't going to just eat a lemon in the shower.'

Hulk stood up. Thankfully, Bruce's pants had stretched enough to accomodate him this time, though his shirt lay in tatters on the floor. 'Banner hate lemons,' he said ruefully. And before Tony could stop him, Hulk had picked up the whole pie in his large hand and stuffed it in his mouth. 'Hulk ike emons,' he mumbled, spraying crumbs everywhere.

Tony put his head in his hands. 'For crying out loud... it still doesn't make sense. It's not like I told JARVIS to make every single cleaning product in the tower citrus-scented-' He froze. 'JARVIS?'

 _'You were a little inebriated at the time I believe, sir_ ,' said JARVIS dryly, ' _but rather enamoured with some lemon-flavoured liqueur.'_

'Wait, so I ordered... everything?'

_'From laundry detergent to dish soap, yes. Though not all contain natural citrus products, clearly some have enough to trigger an allergic reaction.'_

The tap had been running in the lab that day. Bruce must have washed his hands with lemon soap. And there must have been something similar in the shower. And laundry detergent explained the nighttime wanderings - Bruce's bed must be one of the triggers.

'Well, shit. Sorry, Brucie.' He reached up to pat the Hulk's side. 'How long will it take you to burn it off? Wanna help me cook, big guy?'

Hulk shook his head. 'Banner had important thing to say. Need to go back.'

Tony picked up Bruce's spoon and ate a piece of the remaining slice. 'You know what it was?'

He grunted and nodded. 'Banner like you. Good friend. Banner want to make you... special friend.'

'Oh yeah?' He smirked up at him, even as something jumped in his chest. Hopefully not the arc reactor. That would be bad. 'We're already pretty close, big guy. We share measuring cylinders, that's about as close as two people can - '

'Special friend. Kissing friend.' Hulk pressed his finger against the plate that had once held the pie. It cracked under the pressure. He brought the finger to his mouth to lick off the crumbs, not noticing that Tony's mouth had dropped open. 'Lemons good. Make more?'

'I - um - ' He set down the spoon, wiping the back of his mouth. 'No can do buddy, but you know what I could make? Blueberry pie. No citrus in that.'

He grunted, pleased. 'Deal. Hulk go now. Tell Banner stop being coward.' And with a final lemon-scented belch, he started to shrink.

Tony lunged forward to catch him before he hit the floor, and found himself with his arms full of groggy physicist. 'You back with me, Bruce?'

Bruce automatically grabbed his shoulders, wobbling but staying upright. 'Did I hurt anyone?' he slurred.

'No, you're fine, you're fine.' He was suddenly very aware that Bruce was currently shirtless. 'You were only gone for a couple minutes.'

He staggered away with a groan. 'I'm allergic to lemons, I thought I told you?'

'You one hundred percent did _not_ tell me that.' If he'd learned anything since Pepper, it was to remember people's food allergies. 'Since when have you had a citrus allergy?'

'Since always. It's always been pretty bad, but since the other guy showed up I managed to avoid it.' He ran a hand through his hair, leaning against the counter. 'It was a nightmare when I lived in Brazil. It's one of the biggest countries for growing them.' His eyes widened. 'That must be what's causing it! Why else would this be happening?'

_'I'm afraid we have established that Mr Stark ordered for all household products to be lemon-scented. Shall I rescind this order, sir?'_

'If you would, JARVIS.' Tony felt another stab of guilt as Bruce's shoulders hunched, dejected. 'Before he went, ol' Big Green said there was something you wanted to tell me?'

Bruce looked up sharply.

Tony stepped up to him, meeting his gaze calmly.

 _'Speaking of green,'_ DECAF piped up, ' _I have a riddle for you.'_

'Not now, DECAF,' said Tony through gritted teeth. 'Honestly, I made him for you. He's supposed to have more tact than this.'

A faint smile pulled at the corners of Bruce's mouth. 'You made him for _me?'_

_'What's green on the inside, white on the outside, and hops?'_

Tony rolled his eyes and rested his hands on Bruce's bare arms, sliding down until they curled around his elbows. 'A frog sandwich,' he murmured, a thrill going through him as Bruce's throat bobbed in a nervous swallow and his lips parted.

' _Wrong! It's Doctor Banner when he stubs his toe.'_

'I didn't teach him that one,' Tony protested.

But Bruce just laughed, one hand drifting up to brush Tony's cheek. 'It's fine. He has your sense of humour.'

The kiss was hesitant, a gentle press of lips, but Bruce enthusiastically wrapped an arm around his neck to keep him there. Encouraged, Tony pushed their bodies together until he was backed against the counter. 'Anything else you wanna tell me?' he asked when they finally came up for air.

Bruce just blushed and smiled. Then he frowned and licked his lips. 'My mouth has gone numb.' He rubbed at it, his dark eyes fixing on Tony. 'Have you...?'

'Ah, shit. I ate some of it, too.'

'Tony...!' Bruce staggered away from him just as the Hulk burst forth yet again.

'Rargh! Not Hulk fault!' Hulk shouted, in response to whatever Bruce's last thought had been. He looked around the kitchen, then marched up to Tony. He crouched down, looking uncertain. 'Do again?' he asked, pointing at his mouth.

WIth a sigh, Tony reached up on tiptoe to plant a kiss on the top of Hulk's big head. 'Maybe later, big guy. You wanna help me eat some of this until Banner comes back?'

Hulk nodded, beaming. 'Hulk help,' he said graciously, reaching for the plate of brownies.

_'Here's another one! What did the lemon say to the lime?'_

Tony sat down on the counter, defeated.

Hulk frowned. 'Lemons no talk.'

 _'Nothing, silly! Lemons don't - oh, you've heard that one before.'_ DECAF sounded a little put out.

A big green hand reached through the air to pat the little coffee machine. 'S'okay. Tell Hulk another?'

_'With pleasure! Why did the lemon cross the road?'_

Tony popped a brownie in his mouth and smiled.

**Author's Note:**

> So if this story had an explicit rating... would that make it a lemon lemon fic?  
> :0


End file.
